Japanese name:	中馬先生
Nickname:	Chuu-san

Mr. Chuuma is the little-seen and inhumanly apathetic "Club Supervisor" of the Sket Dan spends most of his time in his lab instead of minding them, where his only gift seems to be for creating dangerous and unstable explosive devices. Despite this he has create potions of science fiction effect, such as a youth potion and potions able to change a person's personality,. As his token support is prerequisite to Sket Dan's existence, he holds the threat of its withdrawal over the members' heads when he wishes to coerce them into some unreasonable 'favour'.

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